Tuesday, December 29, 2009

A VERY partial lunar eclipse will take place on New Year's Eve, December 31, 2009, the last of four lunar eclipses in 2009. Only a tiny sliver of the Moon will be in the Earth's umbral shadow, but there should be a distinct darkening visible over the Moon's surface at greatest eclipse.

Thursday, December 17, 2009

On Monday, December 14, S1755 -- The Amateur Radio Emergency Communications Enhancement Act of 2009 -- passed the Senate by unanimous consent; the bill now goes to the House of Representatives for consideration.

U. S. Senators Joe Lieberman (D-CT) and Susan Collins (R-ME) introduced a companion bill to HR 2160 which was introduced to the House of Representatives by Representative Sheila Jackson-Lee (D-TX-18) in April 2009. Senate bill is S1755 is also known as “The Amateur Radio Emergency Communications Enhancement Act of 2009”. More complete information can be found on the ARRL website.

The Main items are;

The first includes; Include a review of the importance of Amateur Radio emergency communications in furtherance of homeland security missions relating to disasters, severe weather and other threats to lives and property in the United States etc.

The second is more interesting; Identify impediments to enhanced Amateur Radio Service communications, such as the effects of unreasonable or unnecessary private land use regulations on residential antenna installations; and make recommendations regarding such impediments for consideration by other federal departments, agencies and Congress.

These is key; if we are ever going to rid ourselves of the overly oppressive Home Owner Association and other antenna restricting rules. -- I highly recommend each of you write your senator and encourage him to explore ways that we can maximize this opportunity here in Georgia.

As many of you already now I love using and tracking repeaters. They are great places for idle QSOs while on long metro commutes which many of us endure. These two repeaters were, and in may ways still are the central hubs to much larger repeater systems, which have continued to dwindle due to the maturing of newer suburban repeaters and clubs.

The Buildings:
The Bank Tower looks and is a much larger building, after all Wikipedia ranks it as the 35th tallest building in the world and the tallest building in North America outside of Chicago and New York City, an impressive pedigree (it is about 1000ft tall).

Meanwhile the AT&T tower is a not meager 677ft. (206-meter), 47-story skyscraper is almost as tall.

On first blush it would seem the Bank of America Tower has a huge advantage as a repeater base, but one must take into account the that the antennas are not at the very top of the building, but closer to the 56th floor roof, the steel structure crowning the building adds height, but all of the antennas are not located at the very top of that structure.

Here is an excerpt from their website to that point; "Our primary antenna for two meters is now located at the base of the "spire" near the building's peak. From this location our antenna has a virtually unrestricted line of sight to most of metro Atlanta." -- There use to be a better picture on the site but I could not find it, and the web statement is barely true.

The Repeaters:
Both of these venerable Atlanta Metro Repeaters are well over 12 years old, and both are starting to show their ages in less than positive ways. Unlike the obvious possible pun from the opening line of a Tale of Two Cities, in the case of these machines I can not really say it "It was the best of times, it was the worst of times…". because in this case it closer to the later than the former.

The w4PME 2m repeater is a Motorola 5000 (tube type transmitter) running about 60 watts output, but capable of over 320 watts continuous! -- recently this machine is suffering some sort of slow death by meltdown, although it still has an impressive coverage area it has frequent temperature lock outs in mid QSO, and this makes difficult to use.

The theoretically equally potent w4DOC 2m repeater is a Vertex VXR-5000 repeater, controlled by a Link Communications RLC-3 controller hybrid with many receivers, a restricted-by-request transmit power of about 45 watts output (see ke4FOV's excellent presentation). -- Recently this machine has taken to not working very well, specially in wet weather. Its average effective range has shrunk to almost the size of the i-285 perimeter, on rainy days it's less.

Both machines have remote listener repeaters located at Sweat Mountain. This accounts for the extended northern lobes in their coverage map.

I wish to bring an awareness to these repeaters; which both seem to be running a fever, and are in need of dire medical attention. -- Please use them, and please contact the clubs that operate them. Upon contacting the clubs offer your support and your positive criticism of the recent decay of these once proud HAM pinnacles. Let them know we value and miss these repeaters.